It can be done, but the ease or complexity depends on how the existing units are piped. The biggest problem will be that the chimney at the new location is sized for just that boiler and water heater, so you will either have to install a second one for the moved units or a larger one for all four systems.

: I just bought an old house that is currently a duplex. There is a gas boiler and water heater in the middle of a finished basement area and another set in a utility area of the basement. I was wondering what would be involved in moving the boiler and water heater near the other set in the utility area. There is a chimney where the second boiler vents now. Can these be moved fairly easily or is this a major deal? Any idea what the cost might be? I am a bit of a novice so any help would be greatly appreciated.